Thermo King SR-2 SmartReefer2, Руководство по диагностике

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Section 5 – SR-2 Diagnostics
03 CHECK (CONTROL) RETURN AIR SENSOR
Page 1 of 2
Alarm Type Check Alarm
(Shutdown Alarm during a Pretrip Test).
Associated Alarm
Codes Alarm Code 11 Unit Controlling on Alternate Sensor
Alarm Code 13 Sensor Check
Alarm Code 92 Sensor Grades Not Set
Alarm Code 203 Check Display Return Air Sensor
Component Description and Location
This sensor is one of two, dual return air sensors. Both return air sensors must agree within specified limits. The
sensor associated with Alarm Code 03 Check (Control) Return Air Sensor is used for unit control. The sensor is
located next to the display return air sensor in the return air stream. It is a graded sensor.
Circuit Description
The control return air temperature sensor circuit is a two wire circuit. The RTP-01 (+) wire connects the
microprocessor 35 pin sensor connector J3 pin 1 to the blue sensor wire. The RTN-01 (-) wire connects the
microprocessor 35 pin sensor connector J3 pin 2 to the brown sensor wire. The sensor wires are routed in the
Sensor Harness. The sensor is hard wired to the sensor harness.
Considerations
1. If the unit is controlling on return air temperature and a problem occurs with either return air sensor, the unit
will switch to Discharge Air Control and Alarm Code 11 Unit Controlling on Alternate Sensor will be set.
2. Sensor codes must be cleared from the Maintenance Menu before Alarm Code 11 will clear.
3. Sensor grades must be correctly set to the actual grade of the sensor installed. Failure to do so may result
in nuisance sensor alarm codes.
4. Sensors should be positioned to minimize the potential for moisture entry where the wires enter the sensor
shell. Mount sensors with the barrel up and the wires down wherever possible.
How Alarm is Set
1. The sensor is over or under range for a specified time interval. The sensor reading may return to normal.
Only Alarm Code 03 Check (Control) Return Air Sensor is set.
2. The sensor reading is erratic over time but did not go over or under range. Both Alarm Code 03 Check
(Control) Return Air Sensor and Alarm Code 13 Sensor Check are set. This indicates the sensor was
inaccurate but was not over or under range.
3. The sensor grade is set to 5H. Both Alarm Code 03 Check (Control) Return Air Sensor and Alarm Code 92
Sensor Grades Not Set are set.
4. The temperatures of the control return air sensor and display return air sensor twins are not within a
specified range. Alarm Codes 03 Check (Control) Return Air Sensor, 203 Check Display Return Air
Sensor, and 13 Sensor Check are set if the faulty sensor cannot be determined. If the faulty sensor can be
determined, only the alarm code for that sensor and Alarm Code 13 Sensor Check will be set.
5-11
02 February 2005